Over the last fifty years, at least, automatic fire protection systems have become widely employed in various facilities throughout the world as a means to save lives, and to limit damage to physical property in the event of a fire. The design of the components associated with these systems has evolved during this time, and a significant number of different sprinkler head trigger configurations have evolved. These designs typically include a flow valve whose operation is initiated by varying mechanical methods, each of which are responsive to heat.
These varying trigger configurations are activated in response to a predetermined amount of heat, or heat load. When the trigger is subjected to a predetermined heat load, the rigidity of a trigger component is compromised. This trigger component typically takes the form of a fusible link assembly, or a frangible bulb assembly, within the sprinkler head. When the rigidity of the trigger assembly is compromised by heat, it collapses and the sprinkler head valve is opened, thereby allowing the flow of water through the sprinkler head assembly, at a predetermined flow rate, into the building. The sprinkler head assembly may be either surface mounted, partially recessed, or fully recessed. An escutcheon or cover plate is typically used as an aesthetic surface trim piece at the perimeter of the hole in the wall, ceiling or ceiling surface through which the head assembly projects.
Significant financial losses have been sustained by building owners or occupants as a result of tampering with sprinkler head assemblies. This loss most often occurs when an attempt is made by the occupant to use the exposed sprinkler head assembly as a device from which to hang various personal articles, as with a clothes hanger. In particular, most designs incorporate a bail or loop of metal which serves to protect the head from physical impact, and may also form part of the trigger structure. From the perspective of an unknowing or unconcerned person, the bail structure appears to be a convenient hook for a hanger, particularly for airing out or drying wet garments.
As a result of this action by the occupant, the fusible link assembly may become inadvertently dislodged or broken, and consequently water flows through the sprinkler head assembly. The pressure and or flow rate from a sprinkler line is usually much greater than from drinking water supply lines, and thus a very large quantity of water may be discharged inside the building within a relatively short period of time.
This action typically causes significant water damage to the flooring, floor covering, furniture, finishes and fixtures within the affected space, necessitating replacement of those damaged items and materials. In addition, the affected space may include floors beneath the discharged sprinkler line. All of the affected space may not be usable until repaired, representing lost rents or revenue, business interruption losses, and diminished productivity. Additionally, the discharge may also require the replacement of portions of the sprinkler head assembly and a resetting of the sprinkler system by qualified technicians, together with testing and reporting, all at considerable expense. Moreover, unless timely notified of a false alarm, fire rescue and other emergency personnel may respond to an automatic signal transmitted as a result of the sprinkler head activation, incurring costs to the municipality, and possibly the building owner.
A cover for a sprinkler head is disclosed, for example, in International Application PCT/DE2006/000538 to Schnell, for use with a concealed sprinkler head. In Schnell, a cover is ejected by a bimetal strip in the presence of heat. Fully recessed sprinklers, as are disclosed in Schnell, are not as prone to tampering by hangers and the like. Thus, Schnell does not disclose a solution for tampering with exposed sprinkler heads.
Another cover is disclosed in U.S. Pat. No. 3,998,273 to Juliano, again for a recessed head. Juliano provides, instead of the bimetal of Schnell, a magnetic engagement for the cover, where the magnet is retained by glue which melts in the presence of an amount of heat sufficient to activate the sprinkler head.
Thus, Schnell and Juliano provide a cover for sprinkler heads for aesthetic purposes and not to prevent tampering, and are limited to recessed sprinkler head designs. Moreover, each design requires a release mechanism which increases the cost of the device. In addition, the covers, release mechanisms, and attachment means of Schnell and Juliano are integrated into the sprinkler head apparatus. That is, they are installed together with the sprinkler head, and thus are not installable without shutting down the sprinkler system, draining it, physically replacing the heads, and rearming the system. This can be a time consuming and expensive process, which leaves the facility unprotected against fire until all heads can be replaced. Many building require hundreds or thousands of heads, and thus replacing heads is simply not a viable option.
To further discourage or reduce the incidence of tampering, it is desirable to notify a prospective tamperer of the potential danger of their actions. An alarm mechanism is disclosed in International Application PCT/GB01/03775, which provides for the breaking of an electrical connection upon melting soldered connections which secure a cover. This device is not directed to tampering, however, but rather to notify that the cover circuit has melted, indicating a fire. Moreover, the alarm signal is received only at a central location, not near the sprinkler head, and does not signal an undesired condition until it is too late. In addition, this device is also integrated or incorporated into the sprinkler head design.
Accordingly, a need remains for a device which will notify an individual not to tamper with a sprinkler head. Further, it is desired to have a tamper deterring device which works with exposed heads, which are more likely to be tampered with, particularly by a hanger, than recessed heads. In addition, there remains a need for an anti tamper device which can be added to existing fire sprinkler systems without a need for replacing sprinkler heads, shutting down the sprinkler system, or performing any other labor intensive modifications.
The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 CFR §1.56(a) exists.